Dust aerosol impact on regional precipitation over western Africa, mechanisms and sensitivity to absorption properties

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

24

Atmospheric Composition And Structure: Aerosols And Particles (0345, 4801, 4906), Global Change: Regional Climate Change, Atmospheric Composition And Structure: Troposphere: Composition And Chemistry

Scientific paper

We investigate the climatic impact of shortwave and longwave radiative forcing of Saharan dust on the West African monsoon and Sahel precipitation using a regional climate model (RCM) interactively coupled to a dust model and running for the period 1996-2006. Two competing effects are found. First a reduction of monsoon intensity in the lower troposphere induced by the dust surface cooling causes a reduction of precipitation, and second an `elevated heat pump effect' in the higher troposphere induced by the dust diabatic warming causes an increase of precipitation. In the standard model configuration, the net impact of these effects is a reduction of precipitation over most of the Sahelian region (by about 8% on average) except over a Northern Sahel - Southern Sahara band, where precipitation increases. These patterns are very sensitive to the dust absorbing properties, which modulate the intensity of the patterns and the boundary between enhanced and decreased precipitation areas. Finally we show that taking into account dust in the RCM could reduce the model bias compared to available observations.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Dust aerosol impact on regional precipitation over western Africa, mechanisms and sensitivity to absorption properties does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Dust aerosol impact on regional precipitation over western Africa, mechanisms and sensitivity to absorption properties, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dust aerosol impact on regional precipitation over western Africa, mechanisms and sensitivity to absorption properties will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-967464

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.